# -*- coding: utf-8 -*-
"""
This module parses commands exactly the same as the luigi task runner. You must specify the module, the task and task parameters.
Instead of executing a task, this module prints the significant parameters and state of the task and its dependencies in a tree format.
Use this to visualize the execution plan in the terminal.

.. code-block:: none

    $ luigi-deps-tree --module foo_complex examples.Foo
    ...
    └─--[Foo-{} (PENDING)]
        |---[Bar-{'num': '0'} (PENDING)]
        |   |---[Bar-{'num': '4'} (PENDING)]
        |   └─--[Bar-{'num': '5'} (PENDING)]
        |---[Bar-{'num': '1'} (PENDING)]
        └─--[Bar-{'num': '2'} (PENDING)]
            └─--[Bar-{'num': '6'} (PENDING)]
                |---[Bar-{'num': '7'} (PENDING)]
                |   |---[Bar-{'num': '9'} (PENDING)]
                |   └─--[Bar-{'num': '10'} (PENDING)]
                |       └─--[Bar-{'num': '11'} (PENDING)]
                └─--[Bar-{'num': '8'} (PENDING)]
                    └─--[Bar-{'num': '12'} (PENDING)]
"""

import sys
import warnings

from luigi.cmdline_parser import CmdlineParser
from luigi.task import flatten


class bcolors:
    """
    colored output for task status
    """

    OKBLUE = "\033[94m"
    OKGREEN = "\033[92m"
    ENDC = "\033[0m"


def print_tree(task, indent="", last=True):
    """
    Return a string representation of the tasks, their statuses/parameters in a dependency tree format
    """
    # dont bother printing out warnings about tasks with no output
    with warnings.catch_warnings():
        warnings.filterwarnings(action="ignore", message="Task .* without outputs has no custom complete\\(\\) method")
        is_task_complete = task.complete()
    is_complete = (bcolors.OKGREEN + "COMPLETE" if is_task_complete else bcolors.OKBLUE + "PENDING") + bcolors.ENDC
    name = task.__class__.__name__
    params = task.to_str_params(only_significant=True)
    result = "\n" + indent
    if last:
        result += "└─--"
        indent += "    "
    else:
        result += "|---"
        indent += "|   "
    result += "[{0}-{1} ({2})]".format(name, params, is_complete)
    children = flatten(task.requires())
    for index, child in enumerate(children):
        result += print_tree(child, indent, (index + 1) == len(children))
    return result


def main():
    cmdline_args = sys.argv[1:]
    with CmdlineParser.global_instance(cmdline_args) as cp:
        task = cp.get_task_obj()
        print(print_tree(task))


if __name__ == "__main__":
    main()
